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Take two: By employing two equivalents of an aldehyde in an asymmetric organocatalytic domino reaction, the nucleophilic enamine intermediate is also converted into the corresponding iminium species through oxidation with o‐iodoxybenzoic acid. Thus, polyfunctionalized cyclohexene derivatives are formed from two simple starting materials in good yields and stereoselectivities (see scheme; Bn=benzyl, EWG=electron‐withdrawing group). [ABSTRACT FROM AUTHOR]

Diaryl ethers are widespread in biologically active compounds, ligands and catalysts. It is known that the diaryl ether skeleton may exhibit atropisomerism when both aryl rings are unsymmetrically substituted with bulky groups. Despite recent advances, only very few catalytic asymmetric methods have been developed to construct such axially chiral compounds. We describe herein a dynamic kinetic resolution approach to axially chiral diaryl ethers via a Brønsted acid catalyzed atroposelective transfer hydrogenation (ATH) reaction of dicarbaldehydes with anilines. The desired diaryl ethers could be obtained in moderate to good chemical yields (up to 79 %) and high enantioselectivities (up to 95 % ee) under standard reaction conditions. Such structural motifs are interesting precursors for further transformations and may have potential applications in the synthesis of chiral ligands or catalysts. [ABSTRACT FROM AUTHOR]

The combination of a transition-metal catalyst and organocatalyst was designed to achieve a highly enantioselective system for the allylic dearomatization reaction of naphthols with racemic secondary allylic alcohols. The desired β-naphthalenones, bearing an all-carbon quaternary center, were obtained in good yields with high chemo- and enantioselectivities. The cooperative catalytic system, involving a chiral iridium complex and phosphoric acid, provided measurable improvements in yields, and chemo- and enantioselectivities relative to single-catalyst systems. Control experiments indicated that the chiral iridium complex functions as a key species in the control of the absolute configuration, thus enabling the formation of both β-naphthalenone enantiomers by simply employing opposite enantiomeric ligands. [ABSTRACT FROM AUTHOR]